Quantifying migratory capacity and dispersal of the invasive tench (<i>Tinca tinca</i>) in the St. Lawrence River using otolith chemistry

The study of distribution and dispersal invasive fishes is challenging during the early stages invasion. Quantification trace elements incorporated into fish hard parts represents an innovative technique for this task. Otolith chemistry has been used to describe stock structure, migratory behaviour support management several species. We otolith population structure tench (Tinca tinca), invader in St. Lawrence River. Tench movements throughout invaded portion system were reconstructed using a Random Forests algorithm. results showed that, despite presumed limited capacity species, are capable extensive (up 250 km). variability patterns among individuals, including both short- long-distance movements, supports stratified diffusion. Such strategy may explain successful invasion River ecosystem. Our flexible framework ecology its native range, as well other freshwater fishes.